Some hulls perform better with the yam lower unit and others do better with the merc. I truly believe that is the difference in the speed variance on some boats more so than the actual 250 merc 4s vs the yam sho motors themselves.
24’Bass Cat Puma Sts-300 Proxs
23’Gatortrax Gt tunnel hull-200 Suzuki
I have ran both the Sho, Mercury V8 250 and 300. Currently own a 250. 250 sho vs 250 Merc the Sho performance Is better all the way around.
250 sho to Mercury 300 V8 is even. All depends on setup.
I don't think one could go wrong with either.
I chose the SHO because Mercury is still new and bugs have not been worked out yet.
I disagree on your performance assessment.
I had a 250 SHO/26 SHO prop on a 2016 BassCat Puma, I now have a 250 ProXS/24 Fury on a 2022 BassCat Cougar (same hull, different cap). The Mercury is noticeably stronger in both mid range and top speed. Both are good motors, but the Mercury sounds better. Couldn't find a Yamaha, but would have gotten a Mercury anyway as warranty can be extended to 8 years vs. 6 on a SHO.
Hmmmmm.... its your first post and you decide to dig up a thread up from 10/19 to respond to? Sounds like something I would do
If I have to repower it will be determined by three factors as to which I get. 1. Warranty 2. Cost 3. How soon can I get it?
I think you are in pretty good shape with either motor, esp. on the back end when it comes time to sell. I would add though, and it depends a lot on setup, but the Sho does, in general, seem to come out of the hole better. I have a 250 SHO on my 21' bug boat and it launches damn near like a sports car. My buddies Merc 8 runs awesome but a little doggier out of the hole. Again, I do understand setup counts a lot!
Funny words like "seems" and phrases like "I think" hold no water. 2 boats same identical setup will not always have the same performance, just how its always been. Boat building and engine manufacturing just are not that advanced.
And the level of effort to determine which motor and boat is identical, is just not worth the .3 mph or .4 sec holeshot diff. or the .2 mpgs.
So when it seems like something is happening there is normally another reason.
Bryan McDonough
2023 Nitro Z21 XL
Nitro Team
My experience the New Mercury is better until someone flashes the SHO.
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Phillip Arrington
Dover/Goodlettsville Tn
2017 Sponsoring Partners:
C&O Marine, Mercury Marine, Goodlettsville Gun Shop, Cantrell's Market, Motorguide , YETI, Carrot Stix, Yum, GateWay Tire Service Center, StormR, SpoolTek, RodSox, Jewel Bait Company, U.S. Bass, Bobs Machine Shop, Lazyman Hooks, FishBum, Bass Militia, Rayus, and Jenko Fishing.
1999 Triton TR-21PD
Mercury 300R
The year is 2036. This thread has been dead for 13 years when someone digs up it to make their first post. It reads something like, my Tesla is better than both of them.
Broken in and propped right means ZERO! Have to be identical boats, identical set ups, identical weight, identical weight distribution, and same driver in each.
Bryan you are so spot on with this. Many with same brands and setups compare and chase each others performance numbers. Where I live I can go to three different bodies of water with identical loads and identical weather conditions and I will get three sets of RPM and MPH numbers on each body of water. Of course with production boats not everyone is going to weigh the exact same either. Each brand will have it's unicorns that will just be a exception above the majority. One example stands out in my mind. RJ (Dukhntr) had a 198 in Kansas that would just flat out run and I don't know any other 198's that could constantly put out the numbers his 198 did.
My 2015 Ranger Z119C on Milford lake in Kansas would consistently run 72.5 to 73mph. In SD it was a 68mph boat and touched 70 a small handful of times. My skeeter has been the same way. Lake Okoboji in IA I posted my best run ever at 75.9mph. On my SD lakes I usually see 71 - 72. There are so many variables.
When it comes to which engine might be the better performer it's really a simple answer. The one that is running without issues. I've seen them all go down when they shouldn't. I know a guy that got a new vexus last June that has barley got to run it cause his trim isn't functioning properly on his new merc and watched several guys in my club have issues with the new 4 strokes. I can't say it's a merc issue though as everyone has a merc to my 1 Yamaha. All it would take is 1 time for my Yamaha not to run properly and it would be the perception of my club that the Yamahas have issues. Simple fact is they all have issues, will all get different performance, based on small variables, ect.
well comparing speeds on different days , diff temps, diff humidity is also not accurate on a naturally aspirated motor. Just so many variables to consider.
Bryan McDonough
2023 Nitro Z21 XL
Nitro Team